CN1847811A - A method for determining the fundamental oscillation frequency in an optical fibre and an application of a tensile force thus measured - Google Patents
A method for determining the fundamental oscillation frequency in an optical fibre and an application of a tensile force thus measured Download PDFInfo
- Publication number
- CN1847811A CN1847811A CNA2006100662962A CN200610066296A CN1847811A CN 1847811 A CN1847811 A CN 1847811A CN A2006100662962 A CNA2006100662962 A CN A2006100662962A CN 200610066296 A CN200610066296 A CN 200610066296A CN 1847811 A CN1847811 A CN 1847811A
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- China
- Prior art keywords
- optical fiber
- spectrum
- oscillation frequency
- draw
- fundamental oscillation
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Classifications
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L5/00—Apparatus for, or methods of, measuring force, work, mechanical power, or torque, specially adapted for specific purposes
- G01L5/04—Apparatus for, or methods of, measuring force, work, mechanical power, or torque, specially adapted for specific purposes for measuring tension in flexible members, e.g. ropes, cables, wires, threads, belts or bands
- G01L5/042—Apparatus for, or methods of, measuring force, work, mechanical power, or torque, specially adapted for specific purposes for measuring tension in flexible members, e.g. ropes, cables, wires, threads, belts or bands by measuring vibrational characteristics of the flexible member
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- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B37/00—Manufacture or treatment of flakes, fibres, or filaments from softened glass, minerals, or slags
- C03B37/01—Manufacture of glass fibres or filaments
- C03B37/02—Manufacture of glass fibres or filaments by drawing or extruding, e.g. direct drawing of molten glass from nozzles; Cooling fins therefor
- C03B37/025—Manufacture of glass fibres or filaments by drawing or extruding, e.g. direct drawing of molten glass from nozzles; Cooling fins therefor from reheated softened tubes, rods, fibres or filaments, e.g. drawing fibres from preforms
- C03B37/0253—Controlling or regulating
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B37/00—Manufacture or treatment of flakes, fibres, or filaments from softened glass, minerals, or slags
- C03B37/01—Manufacture of glass fibres or filaments
- C03B37/02—Manufacture of glass fibres or filaments by drawing or extruding, e.g. direct drawing of molten glass from nozzles; Cooling fins therefor
- C03B37/025—Manufacture of glass fibres or filaments by drawing or extruding, e.g. direct drawing of molten glass from nozzles; Cooling fins therefor from reheated softened tubes, rods, fibres or filaments, e.g. drawing fibres from preforms
- C03B37/029—Furnaces therefor
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B2205/00—Fibre drawing or extruding details
- C03B2205/40—Monitoring or regulating the draw tension or draw rate
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B2205/00—Fibre drawing or extruding details
- C03B2205/60—Optical fibre draw furnaces
- C03B2205/72—Controlling or measuring the draw furnace temperature
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- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Manufacturing & Machinery (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Materials Engineering (AREA)
- Organic Chemistry (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Manufacture, Treatment Of Glass Fibers (AREA)
- Force Measurement Appropriate To Specific Purposes (AREA)
- Measurement Of Mechanical Vibrations Or Ultrasonic Waves (AREA)
Abstract
A method for determining the fundamental oscillation frequency in an optical fibre during the drawing thereof from an optical preform, the oscillation of the optical fibre being measured perpendicular to the longitudinal axis thereof for the formation of a frequency spectrum using Fast Fourier Transformation (FFT), from which the fundamental oscillation frequency is determined, the method comprising the following steps: i) the determination of the frequency spectrum, ii) the mathematical processing of a number of spectra as determined in step i) to obtain a composite spectrum, iii) the re-determination of the spectrum, iv) the removal of the oldest spectrum from the composite spectrum, v) the mathematical processing of the spectrum according to iv) and the spectrum obtained according to iii) to obtain the composite spectrum, vi) the determination of the fundamental oscillation spectrum from the composite spectrum, vii) the repetition of steps iii)-vi).
Description
Technical field
The present invention relates in the method for during the optical precast product drawing optical fiber, determining fundamental oscillation frequency in the optical fiber, the vibration of optical fiber is measured by the longitudinal axis perpendicular to optical fiber, to form frequency spectrum, determine the fundamental oscillation frequency by this frequency spectrum with Fast Fourier Transform (FFT) (FFT).The invention still further relates to the specialized application of the fundamental oscillation frequency that records in this way, in this specialized application, the fundamental oscillation frequency can be converted into tension force.
Background technology
Said method itself is from U.S. Pat 4,692, and 615 as can be known, promptly during pulling process by determining that the fundamental oscillation frequency determines tension force in the optical fiber by means of Fast Fourier Transform (FFT) then.From this patent documentation as can be known, the vibration behavior of optical fiber during drawing is equivalent to vibration or the oscillation behavior of the fixing cotton rope (string) in two ends when tension.Find that according to this known method optical fiber laterally moving during pulling process can be divided into many harmonic wave segmentations (harmonic partition), the frequency of these harmonic wave segmentations is relevant with the tension force in the optical fiber.Thus, the frequency analysis of moving of optical fiber transverse vibration is used to determine tension force, wherein, drawing speed under the constant furnace temperature and tension force is linear dependence to each other.Therefore, by using linear regression model (LRM), can further improve the precision of the frequency approach of this monitoring tension force to measured value.Yet the tension force of being determined by this method confirms to have demonstrated sizable broadening (spread) in practice, thereby, can not accurately determine the fundamental oscillation frequency by the FFT spectrum that obtains like this.
The method of determining the fundamental oscillation frequency with FFT is by U.S. Pat 5,079, and 433 also can know, according to this patent documentation, the second harmonic oscillation frequency are applied extra check.The defective of this second harmonic oscillation frequency is that it has peak level in practice, and this peak level is than the low several magnitude of fundamental oscillation frequency, thereby is difficult to determine it in frequency spectrum.
When manufacturing is used for the glass fibre of telecommunications or data communication, be drawn into the glass fibre that diameter is 125 μ m by the heating prefabricated component.In this manufacturing step, prefabricated component is put into stove lentamente, then prefabricated component is heated to about 2000 ℃.In stove, the prefabricated component fusion is drawn as glass fibre subsequently, and glass fibre leaves heating furnace at the other end.The glass fibre that cooling forms provides protective finish, is wrapped on the spool then.From the used tension force of heating furnace drawing optical fiber is a very important parameters, and it partly determines the intensity and the optical property of optical fiber.
Before providing protective finish to glass fibre, glass fibre is very easy to suffer damage.Infringement can slacken the intensity of glass fibre, makes its easy fracture, and this does not expect.Therefore, reduce the optical fiber of not protected by means of known clean room (clean-room) technology and pass the interior dust concentration in zone.Yet all optical fiber that obtain from a prefabricated component or the most of optical fiber that obtains from a prefabricated component are too fragile usually and can not do further processing.
Such optical fiber carried out microscopic analysis show, this normally since the trickle scratch on the optical fiber cause.It is believed that this is because the parts in the optical fiber the protect contact draw tower, perhaps for example the interior glass fragment of cooling tube or tiny glass fiber granules cause.Although can take some preventive measure before pulling process, for example visual detection or use the brush cleaning cooling tube often still can produce fragile optical fiber.
Summary of the invention
Therefore, a target of the present invention provides a kind of method, makes in this way, and the tension force of optical fiber can accurately be determined during making optical fiber.
Another target of the present invention provides a kind of method, the information whether this method can provide optical fiber during the relevant fiber draw process to contact with the element that uses in the draw tower.
Another target of the present invention provides a kind of method, and this method can provide some process status such as the temperature during the relevant fibre-optical drawing and/or draw the information of speed.
As the method that begins the part indication is characterised in that this method comprises the steps:
I) determine frequency spectrum;
Ii) mathematics manipulation is by step I) definite a plurality of wave spectrums, obtain synthetic spectrum;
Iii) redefine wave spectrum;
Iv) remove the wave spectrum of the oldest (oldest) from synthetic spectrum;
V) the wave spectrum that v) obtains according to step I of mathematics manipulation and according to the wave spectrum that step I ii) obtains obtains synthetic spectrum;
Vi) determine the fundamental oscillation frequency from synthetic spectrum, and
Vii) if desired, repeating step iii)-vi).
Thus, the inventor has worked out a kind of method, adopts this method verified, can be when making optical fiber, determine the reliable value of fundamental oscillation frequency, the perhaps tension force in the correlation parameter, particularly optical fiber based on " vibration cotton rope method ".On the path L in draw tower, the fundamental vibration that optical fiber has is corresponding to according to concerning T=(2.L.f)
2. the tension force of μ, (T=tension force, L=drift, f=oscillation frequency, the line density of μ=optical fiber).Thereby,, can accurately determine tension force assisting down of synthetic spectrum.By removing the oldest measured value continuously, and replenish synthetic composing, thereby obtain stable measured value with the new measured value of removing time-frequency spectrum from synthetic spectrum.According to this method, the vibration of vertical axes measuring optical fiber or vibration.Assisting down of fft analysis, determine a plurality of continuous in chronological order frequency spectrums of this vibration.Then, with a plurality of these frequency spectrum additions or multiply each other, the result of this mathematics manipulation obtain (contrast-rich) peak value in the middle of the contrast of frequency spectrum, thereby the position of this peak value can be determined in simple mode.In the present invention, use the middle peak value of this contrast, be also referred to as the fundamental oscillation frequency.The arrangement that is used for aforementioned mathematics manipulation must spend except the newest frequency spectrum continuous supplementation of old frequency spectrum, so just can be formed on the stably measured method that can use continuously during the optical fiber manufacturing.
In a particular embodiment, the synthetic spectrum of expectation is synthetic by at least 5 independent wave spectrums, especially, and by 20 independent wave spectrums are synthetic at the most.By form synthetic spectrum by at least 5 independent wave spectrums, can suppress broadening, particularly tension measurements in the middle peak value of contrast significantly.When using when carrying out this mathematics manipulation, observe broadening and do not improve significantly more than 20 independent wave spectrum.For method of the present invention, also can replenish by a plurality of continuous results are averaged, such result is that broadening can further be reduced.
The inventor has been found that when optical fiber is run into something or touched something during pulling process, will cause the shortage in the fundamental oscillation frequency of survey frequency scope inner fiber.Find that also the discontinuous operation of optical fiber will cause the figure of fundamental oscillation frequency that significant the variation taken place in practice, the fundamental oscillation frequency is determined as mentioned above.During pulling process, the fundamental oscillation frequency can be apparent on the monitor by image conversion continuously, like this, and down auxiliary at computing machine and software, whether the existence that can also observe the fundamental oscillation frequency produces alarm (audible alarm or visible alarm) when the fundamental oscillation frequency lacks.By this way, the employee can check draw tower when lacking the fundamental oscillation frequency during pulling process, sees that whether optical fiber is freely moving, and can stop pulling process at any time if desired.Thereby this can be avoided producing the optical fiber that does not satisfy required specification.
The tension force that applies during fiber draw process partly depends on the speed that temperature in the heating furnace and optical fiber are pulled out from heating furnace.In the heating furnace of higher temperature, it is softer that the material of optical fiber can become, tension force thereby can reduce.If adopt higher drawing speed, then more tension force can be applied on the optical fiber, and tension force can uprise.Under the method according to this invention, the fundamental oscillation frequency determines according to accurate method, and is therefore verified, can regulate draw machines and/or draw the temperature of speed.
The invention still further relates to method of temperature in a kind of adjusting draw machines, wherein in draw machines, optical precast product at one end heats, optical fiber draws out from this fire end afterwards, according to this control method, fundamental oscillation frequency of Que Dinging or relevant parameter such as the tension force temperature that is used to regulate draw machines as mentioned above.
The present invention also relates to a kind of method that is adjusted in the drawing speed of draw tower inner fiber, according to this control method, optical precast product at one end heats in draw machines, optical fiber draws out from this fire end afterwards, and fundamental oscillation frequency of determining as the inventive method or relevant parameter such as tension force are used to regulate and draw speed.
The present invention relates to a kind of optical fiber of checking in addition and passes the method for draw tower, optical precast product at one end heats in draw machines, optical fiber draws out from this fire end afterwards, and fundamental oscillation frequency of determining as the inventive method or relevant parameter such as tension force are used to check that optical fiber freely passes draw tower.
The correlation parameter that the present invention also relates to the fundamental oscillation frequency or measure according to the inventive method such as the concrete application of tension force, described as appended claims.
Description of drawings
Fig. 1 shows FFT frequency spectrum (position is to the time).
Fig. 2 shows FFT frequency spectrum (position is to the time).
Fig. 3 shows the FFT frequency spectrum, and (position is to the time.
Wherein Fig. 1 and Fig. 2 are comparative examples and Fig. 3 is according to embodiments of the invention.
Embodiment
Below, will further specify the present invention referring to some examples, yet the present invention should not be limited to these concrete examples.
Comparative example
Assisting down of commercially available diameter sensor, measure the position of draw tower inner fiber under the special time.Particularly, in 5 to 30 seconds, determine the FFT wave spectrum by 1024 samples.The position of sensor measurement optical fiber between heating furnace and applicator, optical fiber is provided protective finish at the applicator place.The fundamental oscillation frequency that path L had between the point of the prefabricated component formation of optical fiber in the heating furnace and point that optical fiber is provided the protective finish place is equivalent to according to concerning 2. μ (T=tension force of T=(2.L.f); the L=drift; f=oscillation frequency, the line density of μ=optical fiber) tension force that obtains.By these data (position and time relationship), under FFT auxiliary, make frequency spectrum, as illustrated in fig. 1 and 2.
In the wave spectrum of not only Fig. 1 but also Fig. 2, be difficult to determine accurate peak value corresponding to optical fiber fundamental oscillation, each of Fig. 1 and Fig. 2 all representing in the pulling process different constantly.By the aforementioned relation that adopts different averagings and be used for tension force, can under stable manufacturing state, obtain standard deviation and approximately only be the measured value of 30% tension force, this value is unacceptable in practice.
Embodiment (according to the present invention)
Determine the frequency spectrum of optical fiber in the mode identical with comparative example.But, store a plurality of continuous wave spectrums and also multiply each other each other.By between 5 to 10 wave spectrums, multiplying each other each other, obtain synthetic spectrum, in this synthetic spectrum, can observe tangible peak value, as shown in Figure 3.
Multiply each other and removed the wave spectrum of old wave spectrum by during fiber draw process, replenishing, during pulling process, just can obtain successive measurements, the synthetic spectral representation of this usefulness Fig. 3 with new wave spectrum.Adopt formula commonly used, but go out tension force to the position calculation of frequency peak by clear view in this wave spectrum that multiplies each other.Have about 10% standard deviation at the measured value of stablizing the tension force that obtains like this under the manufacturing state, this value is significantly less than the value that obtains in comparative example.
By the tension value that will obtain thus on average many times, resulting broadening can further reduce.Can make for average ten times broadening further be reduced to 5%.
Claims (15)
1. one kind is used in the method for determining fundamental oscillation frequency in the optical fiber during the optical precast product drawing optical fiber, wherein the vibration of described optical fiber is measured by the longitudinal axis perpendicular to optical fiber, and form frequency spectrum with Fast Fourier Transform (FFT) (FFT), thereby determine the fundamental oscillation frequency by this frequency spectrum, it is characterized in that described method comprises the steps:
I) determine frequency spectrum;
Ii) mathematics manipulation is by step I) definite a plurality of wave spectrums, obtain synthetic spectrum;
Iii) redefine wave spectrum;
Iv) remove the oldest wave spectrum from synthetic spectrum;
V) the wave spectrum that v) obtains according to step I of mathematics manipulation and according to the wave spectrum that step I ii) obtains obtains synthetic spectrum;
Vi) determine the fundamental oscillation frequency from synthetic spectrum, and
Vii) repeating step iii)-vi).
2. method according to claim 1 is characterized in that at step I i) and step v) in used mathematics manipulation comprise these wave spectrums carried out addition or multiply each other.
3. according to the described method of aforementioned arbitrary or a plurality of claim, it is characterized in that described synthetic spectrum comprises at least 5 independent wave spectrums.
4. according to the described method of aforementioned arbitrary or a plurality of claim, it is characterized in that described synthetic spectrum comprises 20 independent wave spectrums at the most.
5. according to the described method of aforementioned arbitrary or a plurality of claim, it is characterized in that described tension force is definite by described fundamental oscillation frequency.
6. method according to claim 5 is characterized in that described tension force is according to concerning T=(2.L.f)
2. μ (T=tension force, L=drift, f=oscillation frequency, the line density of μ=optical fiber) determines.
7. regulate method of temperature in the draw machines for one kind, wherein in draw machines, optical precast product at one end heats, optical fiber draws out from this fire end afterwards, it is characterized in that the temperature that is used to regulate draw machines by the fundamental oscillation frequency of determining as any or a plurality of described method among the claim 1-4.
8. method that is adjusted in the drawing speed of draw tower inner fiber, according to this control method, optical precast product at one end heats in draw machines, optical fiber draws out from this fire end afterwards, it is characterized in that, be used to regulate drawing speed by the fundamental oscillation frequency of determining as any or a plurality of described method among the claim 1-4.
9. check that optical fiber passes freely through the method for draw tower for one kind, according to this inspection method, optical precast product at one end heats in draw machines, optical fiber draws out from this fire end afterwards, it is characterized in that being used to check that by the fundamental oscillation frequency of determining as any or a plurality of described method among the claim 1-4 optical fiber freely passes draw tower.
10. according to the application of fundamental oscillation frequency in the temperature of regulating draw machines of measuring as any or a plurality of described method among the claim 1-4, wherein optical fiber draws out from an end of optical precast product heating in this draw machines.
11. according to the application of fundamental oscillation frequency in the drawing speed of regulating the draw tower inner fiber of measuring as any or a plurality of described method among the claim 1-4, wherein optical precast product at one end heats in draw machines, and optical fiber draws out from this fire end afterwards.
12. checking that according to the tension force of measuring as any or a plurality of described method among the claim 1-4 optical fiber passes the application in the draw tower, wherein in draw tower, optical precast product at one end heats in draw machines, optical fiber draws out from this fire end afterwards.
13. according to the temperature that the tension force of measuring as any or a plurality of described method among the claim 5-6 is applied to regulate draw machines, wherein optical fiber draws out from an end of optical precast product heating in this draw machines.
14. according to the application of fundamental oscillation frequency in the drawing speed of regulating the draw tower inner fiber of measuring as any or a plurality of described method among the claim 5-6, wherein optical precast product at one end heats in draw machines, and optical fiber draws out from this fire end afterwards.
15. checking that according to the tension force of measuring as any or a plurality of described method among the claim 5-6 optical fiber passes the application in the draw tower, wherein in draw tower, optical precast product at one end heats in draw machines, optical fiber draws out from this fire end afterwards.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| NL1028655A NL1028655C2 (en) | 2005-03-30 | 2005-03-30 | Method for determining the fundamental oscillation frequency in an optical fiber, and application of a tensile force so measured. |
| NL1028655 | 2005-03-30 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1847811A true CN1847811A (en) | 2006-10-18 |
| CN100535621C CN100535621C (en) | 2009-09-02 |
Family
ID=35406419
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB2006100662962A Active CN100535621C (en) | 2005-03-30 | 2006-03-30 | A method for determining the fundamental oscillation frequency in an optical fibre and an application of a tensile force thus measured |
Country Status (6)
| Country | Link |
|---|---|
| US (1) | US7228245B2 (en) |
| EP (1) | EP1707933B1 (en) |
| CN (1) | CN100535621C (en) |
| AT (1) | ATE518123T1 (en) |
| DK (1) | DK1707933T3 (en) |
| NL (1) | NL1028655C2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101236116B (en) * | 2008-02-28 | 2011-09-07 | 中铁大桥勘测设计院有限公司 | Method for determining stranded stayed single cable initial tensioning force |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20080307419A1 (en) * | 2007-06-06 | 2008-12-11 | Microsoft Corporation | Lazy kernel thread binding |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6002472A (en) * | 1997-03-18 | 1999-12-14 | The Furukawa Electric Co., Ltd. | Method of measuring optical fiber drawing tension |
| CN1223833C (en) * | 2001-02-28 | 2005-10-19 | 古河电气工业株式会社 | Method of measuring optical fiber drawing tensile force |
-
2005
- 2005-03-30 NL NL1028655A patent/NL1028655C2/en not_active IP Right Cessation
-
2006
- 2006-03-27 DK DK06075708.5T patent/DK1707933T3/en active
- 2006-03-27 AT AT06075708T patent/ATE518123T1/en not_active IP Right Cessation
- 2006-03-27 EP EP06075708A patent/EP1707933B1/en active Active
- 2006-03-29 US US11/277,802 patent/US7228245B2/en active Active
- 2006-03-30 CN CNB2006100662962A patent/CN100535621C/en active Active
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101236116B (en) * | 2008-02-28 | 2011-09-07 | 中铁大桥勘测设计院有限公司 | Method for determining stranded stayed single cable initial tensioning force |
Also Published As
| Publication number | Publication date |
|---|---|
| DK1707933T3 (en) | 2011-10-17 |
| EP1707933A1 (en) | 2006-10-04 |
| ATE518123T1 (en) | 2011-08-15 |
| NL1028655C2 (en) | 2006-10-03 |
| US7228245B2 (en) | 2007-06-05 |
| US20060224270A1 (en) | 2006-10-05 |
| EP1707933B1 (en) | 2011-07-27 |
| CN100535621C (en) | 2009-09-02 |
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